1. Field of the Invention
The present invention relates to a thermal spray powder including ceramic particles.
2. Description of the Related Art
In the field of fabrication of semiconductor devices or the like, the surface of a semiconductor substrate is generally subjected to fine processing by dry etching using plasma of a halogen gas such as fluorine, chlorine, and bromine. After the dry etching, the interior of the chamber from which the semiconductor substrate has been removed is cleaned using oxygen gas plasma. At this time, parts inside the chamber which are exposed to highly reactive oxygen gas plasma or halogen gas plasma can be eroded. Where the eroded portions fall off in the form of particles from the parts, the particles can become a foreign matter (the foreign matter is referred to hereinbelow as “particulate”) that adheres to the semiconductor substrate and causes circuit defects.
Therefore, in order to reduce the occurrence of the particulate in the semiconductor device production apparatuses, the parts exposed to plasma of oxygen gas or halogen gas have been conventionally provided with thermal spray coatings of ceramic materials having high resistance to plasma erosion. For example, Japanese Patent Application Publication (JP-A) No. 2002-363724 indicates that a thermal spray coating with resistance to plasma-induced erosion can be formed using granules, which include yttrium oxyfluoride in at least part thereof, as a thermal spray material. The conventional techniques relating to thermal spray materials formed of ceramics are described, for example, in JP-A No. 2002-363724, 2002-302754, and 2006-225689.